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The same cause as in the arm, viz. a continuance of a large proportion of fleshy fibres to the lower end of the muscles, coextensive with the thigh, gives a great circumference to that segment of the limb above the knee-joint, and a more uniform size to it than in man. The relative shortness of the thigh, its bone being only eight-ninths the length of the humerus (in man the humerus averages five-sixths the length of the femur), adds to the appearance of its superior relative thickness. Absolutely the thigh is not of greater circumference at its middle than is the same part in man.

The chief difference in the leg, after its relative shortness, is the absence of a 'calf,' due to the non-existence of the partial accumulation of carneous fibres in the gastrocnemii muscles, causing that prominence in the type-races of mankind. In the gorilla the tendo-achillis not only continues to receive the 'penniform' fibres to the heel, but the fleshy parts of the muscles of the foot receive accessions of fibres at the lower third of the leg, to which the greater thickness of that part is due, the proportions in this respect being the reverse of those in man. The leg expands at once into the foot, which has a peculiar and characteristic form, owing to the modifications favouring bipedal motion being superinduced upon an essentially prehensile, quadrumanous type. The heel makes a more decided backward projection than in the chimpanzee; the heel-bone is relatively thicker, deeper, more expanded vertically at its hind end, besides being fully as long as in the chimpanzee. This bone, so characteristic of anthropoid affinities, is shaped and proportioned more like the human calcaneum than in any other ape. The malleoli do not make such well-marked projections as in man; they are marked more by the thickness of the fleshy and tendinous parts of the muscles that pass near them, on their way to be inserted into parts of the foot. Although the foot be articulated to the leg with a slight inversion of the sole, it is more nearly plantigrade than in the chimpanzee or any other ape. The hallux (great toe, thumb of the foot), though not relatively longer than in the chimpanzee, is stronger; the bones are thicker in proportion to their length, especially the last phalanx, which in shape and breadth much resembles that in the human foot. The hallux in its natural position diverges from the other toes at an angle of 60 deg. from the axis of the foot; its base is large, swelling into a kind of ball below, upon which the thick callous epiderm of the sole is continued. The transverse indents and wrinkles show the frequency and freedom of the flexile movements of the two joints of the hallux; the nail is small, flat and short. The sole of the foot gradually expands from the heel forward to the divergence of the hallux, and seems to be here cleft, and almost equally, between the base of the hallux and the common base of the other four digits. These are small and slender in proportion, and their beginnings are enveloped in a common tegumentary sheath as far as the base of the second phalanx. A longitudinal indent at the middle of the sole, bifurcating—one channel defining the ball of the hallux, the other running towards the interspace between the second and third digit,—indicates the action of opposing the whole thumb (which seems rather like an inner lobe or division of the sole), to the outer division terminated by the four short toes. What is termed the 'instep' in man is very high in the gorilla, owing to the thickness of the carneo-tendinous parts of the muscles as they pass from the leg to the foot over this region. The mid-toe (third) is a little longer than the second and fourth; the fifth, as in man, is proportionally shorter than the fourth, and is divided from it by a somewhat deeper cleft. The whole sole is wider than in man—relatively to its length much wider—and in that respect, as well as by the off-set of the hallux, and the definition of its basal ball, more like a hand, but a hand of huge dimensions and of portentous power of grasp.

The hairy integument is continued along the dorsum of the foot to the clefts of the toes, and upon the first phalanx of the hallux: the whole sole is bare.

In regard to the outward coloration of the gorilla, only from the examination of the living animal could the precise shades of colour of the naked parts of the skin be truly described. Much of the epiderm had peeled off the subject of the present description; but fortunately in large patches, and the texture of these had acquired a certain firmness, apparently by the action of the alcohol upon the albuminous basis. The parts of the epiderm remaining upon the face indicated the skin there to be chiefly of a deep leaden hue; it is everywhere finely wrinkled, and was somewhat less dark at the prominent parts of the supraciliary roll and the prominent margins of the nasal 'alae:' the soles and palms were also of a lighter colour.

Although the general colour of the hair appears, at first sight, and when moist, to be almost black, it is not so, but is rather of a dusky grey: it is decidedly of a less deep tint than in the chimpanzee (Trogl. niger): this is due to an admixture of a few1 reddish, and of more greyish, hairs with the dusky coloured ones which chiefly constitute the 'pelage:' and the above admixture varies at different parts of the body. The reddish hairs are so numerous on the scalp, especially along the upper middle region, as to make their tint rather predominate there; they blend in a less degree with the long hairs upon the sides of the face. The greyish hairs are found mixed with the dusky upon the dorsal, deltoidal and anterior femoral, regions; but on the limbs, not in such proportion as to affect the impression of the general dark colour, at first view. Near the margin of the vent are a few short whitish hairs, as in the chimpanzee. The epiderm of the back shewed the effects of habitual resting, with that part against the trunk or branch of a tree, occasioning the hair to be more or less rubbed off: the epithelium was here very thick and tough.

It is most probable, from the degree of admixture of different coloured hairs above described, that a living gorilla seen in bright sunlight, would in some positions reflect from its surface a colour much more different from that of the chimpanzee than appears by a comparison of the skin of a dead specimen sent home in spirits. It can hardly be doubted, also, that age will make an appreciable difference in the general coloration of the Troglodytes gorilla.

The adult male gorilla measures five feet six inches from the sole to the top of the head, the breadth across the shoulders is nearly three feet, the length of the upper limb is three feet four inches, that of the lower limb is two feet four inches; the length of the head and trunk is three feet six inches, whilst the same dimension in man does not average three feet.

In the foregoing remarks are given the results of direct observations made on the first and only entire specimen of the gorilla which has reached England. A more important labour, however, remains. The accurate record of facts in natural history is one and a good aim; the deduction of their true consequences is a better. I proceed, therefore, to reconsider the conclusions from which my experienced French and American fellow-labourers in natural history differ from me.

The first—it may be called the supreme—question in regard to the gorilla is, its place in the scale of nature, and its true and precise affinities.

Is it or not the nearest of kin to human kind 1 Does it form, like the chimpanzee and orang, a distinct genus in the anthropoid or knuckle-walking group of apes 1 Are these apes, or are the long-armed gibbons, more nearly related to the genus Homo? O the broad-breast-boned quadrumana, are the knuckle-walkers or the brachiators, i.e. the long-armed gibbons, most nearly and essentially related to the human subject?

At the first aspect, whether of the entire animal or of the skeleton, the gorilla strikes the observer as being a much more bestial and brutish animal than the chimpanzee. All the features that relate to the wielding of the strong jaws and large canines are exaggerated; the evidence of brain is less; its proper cavity is more masked by the outgrowth of the strong occipital and other cranial ridges. But then the impression so made that the gorilla is less like man, is the same which is derived from comparing a young with an adult chimpanzee, or some small tailless monkey with a full-grown male orang or chimpanzee. Taking the characters that cause that impression at a first inspection of the gorilla, most of the small South American monkeys are more anthropoid; they have a proportionally larger and more human-shaped cranium, much less prominent jaws, with more equable teeth.

On comparing the skeletons of the adult males of the gorilla, chimpanzee, orang, and gibbon, the globular cranium of the last, and its superior size compared with the jaws and teeth, seemed to shew the gibbons to be more nearly akin to man than any of the larger tailless apes. And this conclusion had been formed by a distinguished French palaeontologist, M. Lartet, and accepted by a high geological authority at home'. The experienced Professor of Human Anatomy at Amsterdam had been also cited as supporting this view; but I have failed to find any statement of the grounds upon which it was sustained. In the art. Quadrumana of Todd's Cyclopaedia, cited by Lartet2, Professor Vrolik briefly treats of the osteology of the Quadrumana according to their natural families. In 'a first genus, Simia proper, or ape,' he includes the chimpanzee or orang, noticing some of the chief points by which these apes approach the nearest to man. He next goes to the second genus, the gibbon {Hylobates), notices their ischial callosities, and the nearer approach of their molars, in their rounded form, to the teeth of carnivora than the molars of the genus Simia. Then, comparing the siamang with other species of Hylobates, Vrolik says, 'its skeleton approaches most to that of man,' which may be true

1 Sir C. Lyell, Supplement to the 5th Edition of a Manual of Elementary Geology, 1859, p. 15.

3 Comptes Sendus de VAcadimie des Sciences, Juillet 28, 1856.

in comparison with other gibbons, but certainly is not so as respects the higher Simim. No details are given to illustrate the proposition even in its more limited application; but the minor length of the arms in the siamang, as compared with Hylobates lar, was probably the obvious character in Vrolik's mind.

The appearance of superior cerebral development in the siamang and other long-armed apes is due to their small size and the concomitant feeble development of their jaws and teeth. The same appearance makes the small platyrrhine monkeys of South America equally anthropoid in their facial physiognomy, and much more human-like than are the great orangs and chimpanzees. It is an appearance which depends upon the precocious growth of the brain, as dependent on the law of its development. In all quadrumana the brain has reached its full size before the second set of teeth is acquired, almost before the first set is shed. If a young gorilla, chimpanzee, or orang, be compared with a young siamang, of corresponding age, the absolutely larger size and better shape of brain, the deeper and more numerous convolutions of the cerebrum, and the more completely covered cerebellum, unequivocally demonstrate the higher organization of the shorter-armed apes; 'in the structure of the brain,' writes "Vrolik1, in accordance with all other comparative anatomists, 'they' (chimpanzee and orang-utan) 'approach the nearest to man.' The degree to which the chimpanzee and orang so resembled the human type seemed much closer to Cuvier, who knew those great apes only in their immaturity, with their small milk-teeth and precociously developed brain. Accordingly, the anthropoid characters of the Simia satyrus and Simia troglodytes, as deduced from the facial angle and dentition, are proportionally exaggerated in the Eigne Animal2. As growth proceeds, the milk-teeth are shed, the jaws expand, the great canines succeed their diminutive representatives, the biting muscles gain a proportional increase of carneous fibres, their bony fulcra respond to the call for increased surface of attachment, and the sagittal and occipital crests begin to rise: but the brain grows no more; its cranial box retains the size it shewed in immaturity; it finally becomes masked by the superinduced osseous developments in those apes which attain the largest stature and wield the most formidably armed jaws. Yet under this disguise of physical force, the brain is still the better and the larger than is that of the little long-armed ape,

1 Art. Quadrumana, Cyclopedia of Anatomy, Vol. IV. p. 195. 2 Ed. 1829, pp. 87, 89.

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